Fig. 2: Live-cell FLIM-FRET reports the relative OMD dimension in different cell types.

a Representative phasor plot of a large DRG neuron showing the CTxB AF-488/CTxB AF-647 FLIM-FRET. Using the FRET trajectory, the average FRET efficiency is estimated at 0.1. b Representative phasor plot of a cardiac pacemaker cell. Using the same FRET pair and FRET trajectory method, the average FRET efficiency of this cell is estimated at 0.3. c Representative single-cell heatmap images of the membrane-localized FLIM-FRET efficiencies of different cell types as illustrated. d Summary data of the FRET efficiencies of different cell types tested in panel (c) using the CTxB-based FRET pairs: n = 16 cells for tsA cells, as compared to other cell types using one-way ANOVA (no adjustment); n = 10 cells for large DRG neurons, p = 0.6; n = 18 cells for the small DRG neurons, **p = 1e-8; n = 3 cells for hepatocytes, p = 0.1; n = 6 cells for fibroblasts, p = 0.6; n = 8 cells for cardiac pacemakers, **p = 3e-4; n = 5 cells for H9c2 cells, **p = 0.001. The right side of the panel is the summary data of comparable experiments using transiently transfected L10-based FRET pairs: n = 7 cells for tsA cells; n = 6 cells for the large DRG neurons, p = 0.7; n = 8 cells for the small DRG neurons, **p = 2e-4; n = 6 cells for hepatocytes, *p = 0.03. Data shown are mean ± s.e.m., *p < 0.05; **p < 0.01.